According to Microsoft, "this acquisition is a great example of [the company's] commitment to bringing its software and services to all platforms." The company will look to integrate SwiftKey's "core technology across the breadth of our product and services portfolio."

Here are the reasons Microsoft may have bought SwiftKey:

SwiftKey makes big use of artificial intelligence and has, according to the founders, saved an estimated 10 trillion keystrokes by making predictions about upcoming words. (SwiftKey says that's around 100,000 years saved.)

It's hard to quantitatively measure how "cool" or "desirable" Microsoft is under Nadella, but the acquisitions of several high-profile startups — such as Wunderlist — suggests the changes are working, as companies are willing to be purchased by Microsoft.

The acquisition furthers Microsoft's artificial intelligence efforts, image, and reach on iPhone and Android, making it a good deal for the company, and it wouldn't be unreasonable to expect more of these kind of acquisitions in the future.